It’s also important to keep in mind that for 2018, most drug plans — whether as a standalone or as part of an Advantage Plan — have a gap in coverage called the “donut hole.” This gap will disappear in 2019, due to a provision included in the federal budget put in place earlier this year.

Basically, the donut hole this year starts when you have spent $3,750.

If you hit that threshold, you enter the “doughnut hole” and will pay a higher share of drug costs until you reach the so-called catastrophic coverage phase. In 2018, this starts once your annual out-of-pocket drug costs hit $5,000.

Not everyone will ever reach the “donut hole,” and people who get government help paying drug plan costs will not face it. To find out if you qualify for the Extra Help program that helps limited-income households pay for Medicare prescription drug coverage, contact your state’s Medicaid agency or the Social Security Administration.